Process of working down the products arising when coal is liquefied by hydrogenation



'Patented Apr. 23,1929.

UNITED STATES -1,709,957 PATENT OFFICE.

KARL SGHOENEMANN, OF MANNHEIM-RHETNAU, GERMANY.

rnoonss on wonxme Down THE rnonuc'rs ARISING WHEN COAL rs LIQUEFIED BHYDROGENATION.

No Drawing. Application filed December 1, 1926, Serial No. 152,067, andin Germany December 11, 1925.

The oils arising when coal is liquefied by being heated under hydrogenthat is subjected to high pressure (berginization) still containconsiderable amounts of solid substances, viz, the inorganic componentsof the coal and a certain amount of the coal itself. The oils containalso a comparatively large percentage of asphalt, and there arisedifliculties when the solid substances are to be separated from thereaction products. The products may be Worked down, as usually, bydistillation, .it is true, and this .can be effected, with a suitablemanner of operation, without detriment to the oils, but it isunavoidable that also a considerable amount of asphalt arises whichcontains the solid,

- insoluble substances, and the value of which aliphatic hydrocarbon orof aliphatic hydro-- carbons, for instance gas oil, to the coal oilproducts that have-been freed from their light components, as well asfrom water. It is possible when Working with a suitable temperature, toseparate the solid, insoluble substances together with the asphalt in avery sim le manner and the sur )lus oils can be 7 separated from thedeposite merely by decanting, and be worked down further.

This precipitation process can also be carried through in such a mannerthat first the insoluble solid substances are precipitated together witha comparatively small amount of asphalt, whereas the main amount of theasphalt remains suspended or dissolved in the oil present above theprecipitated solid substances. The insoluble components can beseparated, together with a small quantity of asphalt from the liquidpresent above the precipitated substances, by decanting, and theremaining asphalt will then separate and pre cipitate from that liquidwhen left standing then during a certain time in a state in which it isperfectly free from solid components and can again be separated bydecanting from the asphalt-less oil present above it.

only a small amount of asphalt is precipitated together with the solidsubstances, whereas the main amount thereof which is free from solidsubstances, can either be sold or be utilized further in the process.Besides, the distillation of the valuable lubricating oils is notdisturbed by the presence of "considerable amounts of asphalt which are,easily subject to decomposition.

Now the example: 100 kg. of distillation residues having a temperatureof over 280 C. and resulting from berginized pit-coal (softening pointKriimer-Sandow 35, with 25 of undissoluble parts of coal andashes) aremixed at a temperature of 200 C. with 20 kg. of raw petroleum, theresidues being forcibly stirred while the admixing takes place. Afterabout one hour 40 kg. of solid asphalt and undissoluble components willhave been deposited upon the bottom of the mixing chamber. The. oilpresent over the deposit orprecipitate is then withdrawn.

lVithin from 3 to 5 hours thereafter another amount of 40 kg. of softasphalt free from un-.

soluble components separate and precipitate from said oil, and thereremain 4-0 kg. of a thinly liquid, reddishbrown oil which is poor inasphalt. Finally, the precipitation means is re-gained from all threefractional precipitations bybeing blown 0E by means of steam. I

The same procedure can be employed in connection with otherasphalt-containing bituminous materials. It has not been known hithertothat relatively small quantities (such as about 20%) of aliphatic oilscan be used for the separation of asphalt andother impurities. i

In order to re-gain the oil used for the separation of precipitation theboiling limits of that oil may be so chosen that it can be easilyvregained, when the solutions are Worked down, by distillation.

I claim: p 1. The process of working down the products arising when coalis liquefied by hydrogenation, consisting in freeing the productobtained by the liquefaction of the coal from water and from componentshaving a low boiling point, admixing an aliphatic hydrocarbon thereto,and separating the precipitated mixture of asphalt and solid, insolublesubstances from the dissolved mixture of coal oil. and precipitationoil, substantially as set @forth.

2. The process of working down the products arising when coal isliquefied by hydrocom onents and havim been freed from water andcomponents having a low boiling point, and separating the precipitatedmixture of asphalt and solid, insoluble substances from the dissolvedmixture of coal oil and precipitation oil, substantially as set forth.

4:. The process of working down the product obtained when coal isliquefied by hydrogenation, consisting in freeing the product from Waterand from components having a low boiling point, admixing a relativelysmall amount of an aliphatic oil thereto, and separating theprecipitated mixture of asphalt and solid, insoluble substances from thedissolved mixture of coal oil and precipi tation oil, substantially asset forth.

- 5. The process of working down the product obtained Whencoal isliquefied by hydrogenation, consisting in freeing the product water andfrom components having a low boiling point, adinixingan aliphatichydrocarbon thereto, separating from said mixture at first only a smallamount of asphalt together with the insoluble solid substances, allowingthe remaining mixture to settle for an appropriate length of time, andseparating another amount of asphalt, substantially as set forth.

7. The process of working down the products arising when coal isliquefied by hydrogenation, consisting in freeing the product obtainedby the liquefaction of the coal from water and from components having alow boiling point, admixing an aliphatic hydrocarbon thereto, separatingfrom said mixture at first only a small amount of asphalt together withthe insoluble solid substances, allowing the remaining mixture to settlefor an appropriate length of time, and repeating the separation of theasphalt until. the said products have been worked down.

8. The process of working down the products arising when coal isliquefied by hydrogenation, consisting in freeing the product obtainedby the liquefaction of the coal from water and from components having alow boiling point, admixing thereto an aliphatic hydrocarbon, theboilingpoint of which is such that it can be easily re-gaiued, while thesolutions are worked down, by distillation; and separating theprecipitated mixture of asphalt and solid, insoluble substances from thedissolved mixture of coal oil and precipitation oil, substantially asset forth.

In testimony whereof I aflix my signature.

DR. KARL SGHOENEMANN.

